title: Effect of phosphorus availability on the selection of species with different ploidy levels and genome sizes in a long-term grassland fertilization experiment.
abstract: Polyploidy and increased genome size are hypothesized to increase organismal nutrient demands, namely of phosphorus (P), which is an essential and abundant component of nucleic acids. Therefore, polyploids and plants with larger genomes are expected to be selectively disadvantaged in P-limited environments. However, this hypothesis has yet to be experimentally tested. We measured the somatic DNA content and ploidy level in 74 vascular plant species in a long-term fertilization experiment. The differences between the fertilizer treatments regarding the DNA content and ploidy level of the established species were tested using phylogeny-based statistics. The percentage and biomass of polyploid species clearly increased with soil P in particular fertilizer treatments, and a similar but weaker trend was observed for the DNA content. These increases were associated with the dominance of competitive life strategy (particularly advantageous in the P-treated plots) in polyploids and the enhanced competitive ability of dominant polyploid grasses at high soil P concentrations, indicating their increased P limitation. Our results verify the hypothesized effect of P availability on the selection of polyploids and plants with increased genome sizes, although the relative contribution of increased P demands vs increased competitiveness as causes of the observed pattern requires further evaluation.
authors.affiliation: Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Šmarda
authors.affiliation: Faculty of Environmental Sciences, Czech University of Life Sciences, Kamýcká 1176, CZ-16521, Prague 6, Suchdol, Czech Republic.
authors.forename: Michal
authors.initials: M
authors.lastname: Hejcman
authors.affiliation: Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Březinová
authors.affiliation: Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic.
authors.forename: Lucie
authors.initials: L
authors.lastname: Horová
authors.affiliation: Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic.
authors.forename: Helena
authors.initials: H
authors.lastname: Steigerová
authors.affiliation: Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic.
authors.forename: František
authors.initials: F
authors.lastname: Zedek
authors.affiliation: Department of Botany and Zoology, Masaryk University, Kotlářská 2, CZ-61137, Brno, Czech Republic.
authors.forename: Petr
authors.initials: P
authors.lastname: Bureš
authors.affiliation: Institute of Tropics and Subtropics, Czech University of Life Sciences, Kamýcká 129, CZ-16521, Prague 6, Suchdol, Czech Republic.
authors.forename: Pavla
authors.initials: P
authors.lastname: Hejcmanová
authors.affiliation: Institute of Crop Science and Resource Conservation, University of Bonn, Katzenburgweg 5, D-53115, Bonn, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schellberg
mesh_terms: D018744:DNA, Plant; D019143:Evolution, Molecular; D005308:Fertilizers; D059646:Genome Size; D018745:Genome, Plant; D010758:Phosphorus / Q000378:metabolism*; D010944:Plants / Q000235:genetics*; D006109:Poaceae / Q000235:genetics; D011123:Polyploidy; D012641:Selection, Genetic; D012987:Soil / Q000737:chemistry
chemical_list: D018744:DNA, Plant; D005308:Fertilizers; D012987:Soil; D010758:Phosphorus
keywords: DNA content; Rengen Grassland Experiment; flow cytometry; nutrient limitation; phosphorus; plant primary CSR strategies; polyploid ecology; polyploidy